Moving stairway



April 24, 1934. I D. L. LINDQ UIST ET AL 1,956,154

MOVING STAIRWAY Original Filed Sept. 22, 1932 3 Sheets-Sheet l ATTORN EY April 24 1934 D. L. LINDQUIST ET AL 6,

MOV ING STAIRWAY Original Filed Sept. 22, 1932 3 Sheets-Sheet 2 A m 205d V wwmy-mwm CHM LM LAMA 1M2 'm/MA INVENTOES ATTORNEY April 1934 v D. L. LlNDQUlS T ET AL ,9

MOVING STAIRWAY Original Filed Sept. 22, 1932 3 Sheets-Sheet s Mi) 2} u N 5 1457 464 :m 401 1 1-60 II 51 m (H Hm 4 INVENTORS Fatented Apr. 24 19314 Unites STATES PATENT OFFICE- MOVING STAIRWAY David Leonard Lindquist,

Hartsdale, Arthur ration of New Jersey Original application September 22, 1932, Serial Divided and this application June 21, 1933, Serial No. 676,836

2 Claims.

This invention relates" to moving Stairways, and more particularly to certain features involving the steps thereof and the combplate with which the steps cooperate.

Among such features of the moving stairway are the following:

The frame of each step is formed of sheet material, such as steel, pressed into shape so as to provide a curved step riser and a portion upon which removable tread plates are mounted. Each tread plate is preferably die cast from zinc alloy, with the side walls of cleats formed therein. The resulting hollow cleats are filled with a suitable plastic stone, which, after hardening, provides a durable wearing surface for the cleats and one which can withstand considerable abuse. In addition, a completely fireproof step is obtained. If still longer life for the cleats is desired, a corrugated steel strip may be placed on edge in each cleat.

One or more of the step frames is provided with an opening through the tread support so that, when the tread plates for such step or steps are removed, access may be had therethrough to the inner parts of the stairway.

The combplates at the upper and lower landings under which each step passes have their toothed ends vertically adjustable so that the teeth may be made to mesh properly with the I recesses between the cleats in the tread plates on the steps. This vertical adjustment is preferably obtained by rotating each combplate about its base end, where it is suitably supported to permit such rotation. In addition, the toothed end of each combplate is preferably secured to its adjustable supports so that it can quickly be released therefrom without the use of tools. Thus, in an emergency, the combplate can be quickly and readily raised to release anything that may have become wedged between the combplate and astep.

This application is a division of patent application Serial No. 634,338, filed September 22, 1932.

Other features and advantages will become ap: parent from the specification taken in conjunction with the accompanying drawings.

In the drawings:

Figure 1 isa vertical longitudinal section of the upper portion of a moving stairway, with certain parts shown only diagrammatically, and others, irrelevant to this case, omitted entirely;

Figure 2 is a vertical elevation of the upper landing of the stairway, looking in the direction of the lower landing, with certain parts broken away or shown only diagrammatically, and others, irrelevant to this case, omitted entirely;

Figure 3 is a plan view of one of the steps of the moving stairway;

Figure 4 is a vertical elevation of the step shown in Figure 3; c

Figure 5 is a section taken along the line 55 of Figure 4;

Figure 6 is an enlarged plan view of a portion of the step tread of the step illustrated in Figure .3;

Figure 7 is a section taken along the line 77 of Figure 6;

Figure 8 is an enlarged section taken along the line 88 of Figure 6;

Figure 9 is an enlarged plan View of a portion of a step tread illustrating a modified construction for the step tread;

Figure 10 is a section taken along the line 1010 of Figure 9; and

Figure 11 is an enlarged section taken along the line l1--11 of Figure 9.

Referring to Figures 1 and 2, the moving stairway, generally designated 200, extends between a lower landing (not shown) and an upper landing 202, The moving stairway comprisesan endless series of steps 203 driven from main drive shaft 207 by appropriate equipment, including two running gear chains 230 and 630, one at each side of the stairway, and two sprocket wheels 2'75 and 675, each secured to drive shaft 207 and engaging the running gear chains at the corresponding side of the stairway. Two endless moving handrails 208, 608, one at each side of the stairway, likewise are driven from drive shaft 207.

The relation of the two running gear chains to the steps and to the step rollers is most clearly shown in Figures 3 and 4. The single step illustrated, generally designated 203, is shown between a running gear chain 230 at the right thereof and a running gear chain630 at the left thereof. The two running gear chains are similar in construction, each being of the double link roller type, with uniformly spaced chain bushings or rollers, 231 for chain 230 and 631 for chain 100 630, of uniform outside diameter. At every third chain roller in each of the two running gear chains, the chain is provided with a hollow pin, such as pin 632 for chain 630. Connecting the two running gear chains at each of the points 105 therein having such hollow pins, there is a step axle 233 extending across the stairway, through the hollow chain pins, and projecting out beyond each chain. Upon each such projecting portion of each step axle 233 is mounted a chain 110 v of the step frame. frequently two, in a complete moving stairway wheel, the chain wheels adjacent running gear chain 230 being designated 234 while the chain wheels adjacent running gear chain 630 are designated 634. At the extreme ends of each step axle there are two collars 235 and 635, which are retained in position preferably by taper pins driven therethrough and through the step axle. The ends of such pins are split, and after assembly are spread apart. It is preferred that each collar 235 and 635 be provided with a sleeve extending through the chain wheel and on which the chain wheel rotates. This sleeve is of sufficient length and diameter to provide clearance for the chain wheel between the running gear chain and the collar.

As a result of the foregoing construction, the two running gear chains 230 and 630 are connected together at every'third chain link by the series of step axles 233 throughout the entire loops of the two running gear chains.

Each step 203 comprises a step tread 254, a step frame 255 and two step yokes 256 and 656. The step frame is formed of suitable sheet material bent into the shape illustrated in Figure so as to provide a tread support 257 and a curved riser 258. Step tread 254 is preferably made up of a plurality of tread plates each of which is bolted or otherwise secured to tread support 257 A small number of the steps,

preferably have their tread plates secured to tread support 257 by means of screws so that the tread plates may be removed from such steps, and

, replaced thereon, from the exterior of the stairway. The step frames of such steps are formed with an opening therein, illustrated by the dot and dash outline 260 in Figure 3, so that access may be had to the under side of such steps and to the inner parts of the moving stairway when the tread plates have been removed. If desired, however, each step of the stairway may be constructed with such opening therein, and with screwed down tread plates.

The tread plates are preferably constructed with cleat formations as illustrated in Figures 3 and 4. The details of such tread plates will be discussed later in this description.

The two step yokes 256 and 656 are secured to the step frame near the sides of the step, as illustrated in Figures 4 and 5. These two step yokes are conveniently die cast of appropriate zinc alloy and formed with hubs 261 and 661, respectively, of bearings for step axle 233. Each step is secured to its step axle by means of bearing caps 262 and 662 bolted to the hubs of the step yokes. In the event it is desired to remove a step, the two bearing caps 262 and 662 for such step are removed, whereupon such step may be removed from the stairway as a unit. In so removing and replacing a step, it is to be noted that no part of the running gear chains 230. 636 is distrubed. Each step is centered and maintained in position on its step axle 233 by means of spacing sleeves 263 and 663.

At the trailer end of each of the two step yokes 256 and 656, there is mounted a short stub shaft parallel to the step axle 233. On each stub shaft there is provided a trailer wheel rolling in a plane just inside the adjacent side edge of the step. The trailer wheel at the side of the step adjacent chain 230 is designated 264, while the trailer wheel at the side of the step adjacent chain 630 is designated 664.

In the illustrated embodimentof the moving stairway, step yokes 256 and 656 are shaped as illustrated in Figure 5 so that, when the step is on the upper incline run of the stairway, the trailer wheels roll on an inclined plane, indicated at 266 in Figure 5, which is parallel to but below the inclined plane, indicated at 265, on which roll the chain wheels. With such illustrated construction, a perpendicular line extending upwardly through the axis of the trailer wheels is just within the nose of the step. It is thus practically impossible for anyone to stand near the nose of a step in such a manner that he produces any appreciable turning moment tending to rotate the step clockwise about the trailer wheels, as viewed in Figure 5. It is therefore practically impossible for anyone to stand on the step in such a manner that he lifts the chain wheels from the track along which they roll. In addition, as a result of this construction, the weight of a person standing on the step where a person normally would stand thereon is approximately equally distributed between the chain wheels and the trailer wheels.

The preferred construction of the tread plates making up step tread 254 of each step is illustrated in Figures 6, 7 and 8. Each plate comprises an aluminum or zinc alloy die casting 460 provided with upwardly extending portions 461 which form the side walls of the cleats. Reinforcing ribs 462 are provided between the side walls of each individual cleat. The cleats are formed by filling the spaces between the side walls 461 with a suitable artificial stone, preferably a magnesite composition flooring 463, such as asbestolith, when the material is in a plastic state, and allowing it to set in place. A durable non-slip tread surface is thereby obtained. In addition, the resulting tread plate is sound damping and fireproof.

A modified construction for the tread plates is illustrated in Figures 9, and 11. (Incidentally, Figures 9 and 10 are continuations of Figures 6 and 7, respectively, so as to show the construction of casting 460 both at the heel and the nose of the step.) The tread plate is similar to that previously described, but has, in addition, a corrugated steel or other metal strip 464 inserted on edge in each cleat. Such a construction may be employed where the stairway is subjected to very extensive use, or where it is desired to further increase the life of the tread plates.

When mounting the tread plates 460 upon tread supports 257 of the steps. there is preferably interposed between each tread plate and the tread support a filler of fireproof sound-deadening material 465, such as asbestos.

The upper landing is provided with a combplate 360 having combs or teeth 361 which project into the spaces between the cleats of the step treads as the steps pass under the combplate (see Figures 1 and 2). The base end of the combplate is tongued and grooved to a floor plate 362, while the toothed end is supported on suitable shoulders 363 and 763 on pins 364 and 764, respectively, one at each side of the stairway. Pins 364 and 764 are preferably threaded into their respective supporting members so as to provide a vertical adjustment for the teeth of combplate 360. Preferably, also, the stems of the pins above shoulders 363 and 763 are such that the combplate may be raised upwardly off such pins. Normally wedges 365 and 765, extending through suitable slots in pins 364 and 764, respectively, retain the combplate against pin shoulders 363 and 763. As a result of such construction, in the event of an umbrella end or other body becom- 1 50 ing snagged between the teeth of the combplate and a step, the combplate may be raised, the obstruction removed, the combplate replaced and operation of the stairway resumed, all in a minimum of time. In practice, it is customary to provide, proximate to each of the wedges 365 and 765, a small hammer, by means of which one may release the combplate without other tools, and without waiting for the building engineer.

Access is obtained to wedges 365 and 765, which are positioned inside the balustrading, by virtue of the fact that a portion of the bottom panels 323 and 723 is hinged, as shown at 766 for panel 723 in Figure 2. The doors thereby formed extend the length of the combplate so that the combplate may be raised without interference from the bottom panels.

The combplate and related parts at the lower landing are similar to those at the upper landing, and so need not be shown or described.

Inasmuch as many changes could be made in the above constructions and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In combination with a moving stairway in which the tread surfaces of the steps comprise a plurality of cleats; a combplate having teeth opposite the base end thereof adapted to fit between the cleats of the stairway steps; andmeans mounting said combplate at one end of the stairway, with its teeth in the spaces between the cleats of the stairway steps, so that the toothed end of said combplate is vertically adjustable in said spaces, said means comprising, a pivotal support for the base end of said combplate, and vertically adjustable supports for said combplate at either side thereof adjacent its toothed end. 2. In combination with a moving stairway in which the tread surfaces of the steps comprise a plurality of cleats; a combplate having teeth opposite the base end thereof adapted to fit between the cleats of the stairway steps; and means mounting said combplate at one end of the stairway, with its teeth in the spaces between the cleats of the stairway steps, so that it may be quickly released and removed to free anything caught between said combplate and a step, said means comprising, a shoulder rest for the base end of said combplate, supports for the toothed end of said combplate at either side of the stairway, supporting and aligning said combplate in its normal position, at least one of said supports having an extension above the upper surface of said combplate, and a removable wedge interposed between said combplate and said extension for preventing, only when said wedge is in place, the removal of said combplate from said supports.

DAVID LEONARD LINDQUIST.

ARTHUR EDWARD HANDY.

SAMUEL GUSTAVE MARGLES. 

